Carl Trueman (from this article -- and the whole thing is worth reading!):
When I married a young couple in my congregation a few years ago, I commented in the sermon that all human marriages begin with joy but end in tragedy. Whether it is divorce or death, the human bond of love is eventually torn apart. The marriage of Christ and his church, however, begins with tragedy and ends with a joyful and loving union which will never be rent asunder. There is joy to which we point in our worship, the joy of the Lamb’s wedding feast. But our people need to know that in this world there will be mourning. Not worldly mourning with no hope. But real mourning nonetheless, and we must make them ready for that.
J.I. Packer [from “The Gospel and the Lord’s Supper,” in Serving the People of God, vol. 2 of Collected Shorter Writings of J. I. Packer (Carlisle: Paternoster, 1998), 49-50.]:
We are … to learn the divinely intended discipline of drawing assurance from the sacrament. We should be saying in our hearts, ‘as sure as I see and touch and taste this bread and this wine, so sure it is that Jesus Christ is not a fancy but a fact, that he is for real, and that he offers himself to be my Saviour, my Bread of Life, and my Guide to glory. He has left me this rite, this gesture, this token, this ritual action as a guarantee of this grace; He instituted it, and it is a sign of life-giving union with him, and I’m taking part in it, and thus I know that I am his and he is mine forever.’ That is the assurance that we should be drawing from our sharing in the Lord’s Supper every time we come to the table.
And then we must realize something of our togetherness in Christ with the rest of the congregation. . . . [We should reject the] strange perverse idea . . . that the Lord’s Supper is a flight of the alone to the Alone: it is my communion I come to make, not our communion in which I come to share. You can’t imagine a more radical denial of the Gospel than that.
The communion table must bring to us a deeper realization of our fellowship together. If I go into a church for a communion service where not too many folk are present, to me it is a matter of conscience to sit beside someone. This togetherness is part of what is involved in sharing in eucharistic worship in a way that edifies.